Sulfuric Acid → 3,6-Dichloro-4-isopropylpyridazine

HRID 414212Notes

Reaction equation

HRID 414212 reaction equation
[Cl:1][C:2]1[N:3]=[N:4][C:5]([Cl:8])=[CH:6][CH:7]=1.[C:9](O)(=O)[CH:10](C)[CH3:11].S(=O)(=O)(O)O.S(OOS([O-])(=O)=O)([O-])(=O)=O.[NH4+].[NH4+].S(OOS([O-])(=O)=O)([O-])(=O)=O.[OH-].[NH4+]>[N+]([O-])([O-])=O.[Ag+].O>[Cl:1][C:2]1[N:3]=[N:4][C:5]([Cl:8])=[CH:6][C:7]=1[CH:10]([CH3:11])[CH3:9]

Participants

9

Reactant 6

HCID 1118Sulfuric AcidHCID 6590Isobutyric AcidHCID 14923Ammonium HydroxideHCID 62648Ammonium PersulfateHCID 673313,6-DichloropyridazineHCID 107879Peroxydisulfate

Product 1

HCID 140241623,6-Dichloro-4-isopropylpyridazine

Reagents, catalysts & solvents 2

HCID 24470Silver NitrateCatalystHCID 962WaterSolvent3×

Procedure

Fifty g. of 3,6-dichloropyridazine was slurried in 500 ml. of water with 28.5 g. of silver nitrate and 66.5 g. of isobutyric acid at 50°. Five hundred ml. of water and 98.6 g. of sulfuric acid were added, and the mixture was heated to 60°. To it was added 228 g. of ammonium persulfate, dissolved in 500 ml. of water. The mixture warmed to 75° as the persulfate was slowly added, and after the addition the mixture was cooled to 10° and ice was added to it. The pH was then adjusted to 9-10 with ammonium hydroxide, and the mixture was extracted three times with 400 ml. portions of diethyl ether. The organic layers were combined and washed twice with 400 ml. portions of 0.5N sodium hydroxide. The organic layer was then washed with brine, dried over magnesium sulfate, and evaporated under vacuum to obtain 52 g. of impure product. It was chromatographed by high performance liquid chromatography, eluting with 5:1 hexane:ethyl acetate, and the desired product was obtained as an oil, amounting to 25 g.

Workup

  1. customat 50°
  2. temperaturethe mixture was heated to 60°
  3. additionTo it was added 228 g
  4. additionwas slowly added
  5. additionafter the addition the mixture
  6. temperaturewas cooled to 10°
  7. additionice was added to it
  8. extractionthe mixture was extracted three times with 400 ml
  9. washwashed twice with 400 ml
  10. washThe organic layer was then washed with brine
  11. dry with materialdried over magnesium sulfate
  12. customevaporated under vacuum
  13. customto obtain 52 g
  14. customIt was chromatographed by high performance liquid chromatography
  15. washeluting with 5:1 hexane

Sources & evidence

ORD record
ord-f3c9afbd24ac4cc482eefcbeea845b69
Source dataset
uspto-grants-1988_12
Patent number
US04791110

Reaction notes

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